Conveyors



Jan. 22, 1957 Filed Oct. 11, 1954 J. H. FOSTER CONVEYORS 3 Sheets-Sheet 1 INVENTOR.

Josapy H flosrfe J. H. FOSTER Jan. 22, 1957 CONVEYORS 3 Sheets-Sheet 2 Filed 001:. 11, 1954 INVENTOR. J05A4 1 05752 BY Z E A r roe/VH4? J. H. FOSTER CONVEYORS 3 Sheets-Sheet 3 Jan. 22, 1957 Filed Oct. 11, 1954 United States Patent CONVEYORS Joseph Harold Foster, Seattle, Wash.

Application October 11, 1954, Serial No.-461,611 4 (Ilaims. (Cl. 198--218) Burrowing type of mining machines are known and are made in many constructions, these functioning to burrow into and cut away the face of a vein of coal, for example, whereby the loosened coal may be collected and conveyed away. A representative machine of the character mentioned is disclosed in the application of Max B. Kirkpatrick, Serial No. 399,255, filed Dec. 21, 1953, now Patent No. 2,756,037, issued July 24, 1956, with which this conveyor is intended to function. Generally such mining machines are capable of operating at a rate of speed such as to tax the capacity of whatever conveying mechanism it is physically possible to maintain functioning closely behind the advancing mining machine, with the result that the mining machine is seldom able to operate at full capacity, simply because it is not possible to convey away the coal or other values as rapidly as the mining machine can dislodge them from the vein. The present invention aims to provide conveying mechanism which can be maintained without substantial interruption of operations in operative relationship to such a mining machine, and which will function automatically and have a capacity adequate to carry away the loosened values at the rate at which the mining machine can break them loose and can itself advance.

Somewhat more specifically stated, the present invention aims to provide a sectional conveyor of the general nature indicated which can be attached directly to the rear end of the advancing mining machine and either be dragged forwardly by the latter, over a straight or a curved path, and either uphill or down, or the sections whereof can be rolled up into small compass and stowed compactly at the rear of the machine, where they will come successively into operative position as the machine advances, so that the conveyor will always be in position to receive from the mining machine, without the interposition of an operator, the materials which are dislodged by the machine. The conveyor of this invention is arranged in such manner that additional sections as required can be attached to it, to extend its length to any reasonable distance, without limitation.

The present invention contemplates a sectional conveyor in which each sectional unit, separately made and hingedly connected to the sections before and behind, functions by receiving materials from the preceding section while the given section is flat, and then by curling up the given section advances or flips the material upon it onto the next following section, and this in turn flips the material onto the section that follows it. 'Each section after flipping the material onto the following sections returns to its flat condition in time to receive a further load from the section which precedes it. The operations of curling up each section and of uncurling it are preferably performed by the pneumatic inflation 'of bladders which form part of each section, and by their deflation, under control of suitable valves which may be automatically controlled or sequenced.

This invention comprises the novel conveyor section ice 2 and the novel multi-sectional conveyor, as shown in the accompanying drawings in a typical form and as will be more fully described in this specification and defined by the claims.

Figure 1 is an isometric view of two complete and cooperating sectional units, each partially broken away, and of a part of a third unit, illustrating the relationship between the several successive units in such a sectional conveyor, the construction illustrating one form in which the invention may be embodied.

Figure 2 is a longitudinal sectional view through two such conveyor sections and illustrating diagrammatically in dot-dash lines the subsequent delivering position of the section which is shown in full lines in the process of receiving materials.

Figure 3 is a diagrammatic plan view of such a sectional conveyor, showing the manner in which the same may round a curve.

Figure 4 is a plan view, broken away in part, of two adjoining sections of a somewhat difierently constructed conveyor, still embodying the principles of this invention.

Figure 5 is a longitudinal sectional view of the conveyor shown in Figure 4.

The invention is capable of embodiment in the two forms illustrated herein, and others. In the form shown in Figures 1 and 2 the conveyor sections are built up of rubber bladders combined with metal plates, whereas in the form of Figures 4 and 5 the conveyor sections are wholly of rubber or similar material. In either form there is a lower sheet or lamina of substantially slight or no elasticity as a whole, although flexible as a whole in the longitudinal direction, and means defining individual bladders disposed transversely at longitudinally spaced intervals, each with a relatively flexible but nonelastic upper wall. In Figures 1 and 2 the bladders of each section are shown as inflatable and deflatable by means of individual valves, solenoid operated, whereas in Figures 4 and 5 the control is by way of a single fourway valve alternately connecting pressure and vacuum tanks with alternate sections, in a closed circuit. In the form of Figures 1 and 2 the inflexibility of the lower sheet or lamina, and of the bladders lower wall, is achieved by reinforcing the bladders with hingedly joined metal plates, whereas in the form of Figures 4 and 5 a like result is achieved by making the lower sheet of a rubber-like material of greater stiffness than an overlying upper sheet, these two sheets being joined transversely at intervals. Each form has certain advantages. It will be convenient to describe first the form of Figures 1 and 2.

Each section of the conveyor includes a plurality of plates which are generally elongated transversely of the direction of advance, and which are placed in successive edge-to-edge relationship. One such plate 1 rnay be designated the terminal plate, being the last one past which the material moves. Preferably there are an odd number ofsuch plates, there being seven shown herein, which are designated in turn after the terminal plate 1, by the numerals 2, 3, 4, 5, 6 and 7. Such plates are hingedly connected each to the adjoining plates. The

. hinge connections are shown at 1%, 23, 34, 45, 56 and vening or even-numbered plates 2, 4, and 6, are inflatable but substantially inelastic bladders. Since these several bladders of a section should be connected for substantially simultaneous or closely successive inflation, it is convenient toform them: asinfl-a-table sections of. a doublethickness sheet 8= which extends uninterruptedly from the terminal plate 1 to'the most distantplate 7. Thisplate: is secured by any suitable means along the length' of each odd-numbered plate; well inwardly from its edges; For example, an inflation duct 1t} mounted upon the terminal plate 1 secures one edge of the sheets 8, a hold-down plate 30' secures the sheets to the plate 3, a holtbdown plate 50 securesthe sheetsto the plate 5, and a hold-down plate 70 secures the sheets andseals their edges to the plate 7. This leaves the space above each even-numbered plate free to distend. to form the bladders 28, 4-8 and 68, above the respective plates 2, 4 and 6, which bladders overlap at'their edges the hinges of these plates to the adjoining odd-numbered plates. Each bladder is secured to the two odd-numbered plates 3 and 5 along its edges, leaving passageways located outwardly of the ends of hold-down plates and 5%, between the two layers of the sheet 8, similar to the passageways or channels 8a of the form shown in-Figures 4 and 5-, for passage of air from one bladder to the next, and so on to the last. lnflaticnand subsequent venting for deflation-is accomplished through the inflation duct at l0, and internally by way of the passageways just mentioned.

Inflation is under control of a valve 11 connected in the inflation duct 10 and receiving its air supply from an air line or main 12, which should be a flexible hose. Preferably alternate sections" in a multi-section conveyor are controlled for conjoint operation, and the intervening sections are all conjointly controlled. To this. end the valves it may all be connected to the main 1 2, and valves 11a of the intervening sections to a similar Ina-in 1211, or the valves might all be connected to a single main, and controlled alternately. Bysome such control arrangement the bladders of one set of sections may be inflated while those of the intervening sections are deflated,- and vice versa. controlled electrically and, if desired, automatically, but in order to avoid confusing the showing, electrical lines and controls have been omitted.

Theseveral sections are connected, and the terminal plate 1 of each section is held always flat upon the supporting surface, by means such as the drawbar 9 underlying the section as a whole and extending the length of the section and sufficiently beyond toconnect to the terminal plate 1 of an adjoining section. Preferably the drawbars are pivotally connected to'the respective terminal plates, as indicated at 9% and 91, and the drawbarsare located midway between the sides of the section, so that the entire string of sections may be drawn along, one behind the other, yet may pivot transversely of the direction of advance, each with respect to the adjoining sections. Thus the entire string, of conveyors can round curves in the manner illustrated diagrammatically in Figure 3.

When any given section has its plates lying flat; it can receive a load of material upon it. Upon inflation of: its several bladders, the material of which the sheet 8 is formed being substantially nouelastic, these bladders will tend to round out, and so to draw their secured edgestogethcr. These edges are connected to the: odd-numbered' plates, and so tend to draw these plates together and to hinge all the plates about their hinge axes, until the section as a whole curls up into the general. conformation shown at the right in Figure 2; with; the last plate- 7 overlying the section ahead. Since the inflation. begins at the bladder 28 and progresses thence to the bladder 48 and finally to the bladder 68; the material tends to slide as the section is rising toward its: terminal: plate 1,. but as the mechanical advantage improves; and as inflation oh the outer bladdersequals inflation of the: inner bladders, there is an appreciable accelerative action. This The valves 11 or 11a may be solenoid valves 4 may be likened to the flipping of the fingers of a hand, which propels the material on the finger tips and then that on the palm itself forwardly. The material is flipped forwardly and well onto the next section, which at the time lies flat behind the section, the bladders of which are being inflated. As soon as the material has been discharged thus onto the next section, the bladders can be deflated; again, deflation commences from the bladder 28 and proceeds through the: bladder 4-8 and into the bladder 68, and causes these to lie down smoothly, ready receive a further load of materials from the section which precedesit; Thus the material advances by successive flips from one section to the next, with the result that it is removedvery' rapidly, and gives the conveyor good capacity.

It has been found desirable to provide an apron 31 upstanding from the third plate 3, or from its hold-down plate 30,: and. projecting forwardly, of such height that it will stop material which might tend. to over-throw or roll past the apron, an'd: of a length such that when the section is curled: up'it: will, as shown in dotted lines in Figure 2 atthe left or in full lines at the right, overlie the edge of. the terminal. section 1 and so direct all material fro'rn the one section onto: the next section.

Itv has also beenfound desirable to: provide side flanges for retainingt'the material upon each section. These side flanges? if usedwould' ordinarily'be flexible, and it is convenientto form them as upward noninflatable extensions 88 0f the endsrofthe sheet 8. The air passageways betweenthe'several bladders lie inside these side flanges. To assist in' maintaining. these flexible flanges upright one end thereof may besecured to the ends of the apron 31', anddistant therefrom there may be provided a stretchable andabrasion-resistant cord 89 joining the flanges atopposite sides of the" section.

In order tct protect the hold-down plates from abra' sion by the material it has: been found preferable to employ a protective flexible sheet 71 secured by. the: holddown plate 'and" extending. the length of the section, over. the other hold-down plates and beneath the elastic cord-8 9.

The conveyor is shown'in a:simplified form in Figures 4- and- 5, a* form capable of manufacture more simply, and the sections whereof are rather'readily curled up for ease of transportation and handling; It lacks the plates which'stifienthe conveyor" in the f'ornlof Figures 1 and 2, in: the several sections, and the actual: hinges therebetween. Instead, each section is made wholly of a lower sheet of quite stiff and'linela'sti'o' rubber, and an upper sheet 81 of equally inelastic but more readily flexible rubber. These sheets are bonded together about their edges, as indicated at 82,. and at intervals lengthwise they are bonded together, as: at 83; These portions 83 correspondtothe'plates 3 and 5 in the form first described, and the. intervening portions correspond to the plates 2, 4 andx6; and defineth'etinflatable bladders 28a, 48a and 68a. Channels 84 afford communication from the infiationi and deflation: duet 10a to all the bladders, just as, in the: previously described form; like air passageways, similarly located; connect the bladders.

The manner of operation is substantially the same asbefore. Inflation of the bladders causes the sheets 80,. 81 to: curl'up', because of the differential stillness of these sheets. Deflation flattens the sheets. Every othor section: may beconnected to an air line 12b and each intervening section to: an; air line- 12c. A compressor 12dmay draw air from a vacuum tank 120, and compress it into-pressure tank 127. A reversible four-way valve 12g connectsline L25 tovacuum and to pressure, flattening: all sections which. connect to line 12b and curling, up sections which connect to line 120. This condition: is shown in Figures 4 and 5. Upon reversal of the valve 1'2 the formerly flattened sections connected: to' line 12b are; curled up, and the formerly cur-led sections connected to line 12c are flattened. This action can recur rapidly, resulting in a constant flipping advance of relatively small quantities of material, using low air pressure. The closed circuit allows all the air to be dried, and eliminates danger of freezing because of the frequently repeated expansions. The absence of electrical switching devices Within the tunnel eliminates danger of gas explosions.

The several sections in the form of Figures 4 and 5 may be connected flexibly by means such as the draft straps 92 secured to the terminal portion of each section adjacent the bladder 28a, and extending beneath or alongside the section for securement of a hook 93 at its end to ears 94 of the next forward section.

The first section may be secured at the rear end of the mining machine, in position to receive loosened material therefrom. Successive sections trail behind the first section, and as the machine advances, it may drag the string of sections behind it. More sections as needed are added to the trailing end of the string. Alternatively, several sections can be curled up and disposed side by side at the rear end of the mining machine, all connected in succession however, and as the machine advances one such curled section will uncurl and assume its place in the string, then another, and so on until all are in use. This will permit a fairly long uninterrupted advance, before additional curled-upsections must be added at the leading end of the string, and avoids the necessity of dragging the Whole string, or of unloading the string completely to enable it to be dragged, each time the mining machine advances. The sections of the form shown in Figures 4 and 5 are peculiarly suited for curling up thus when not in use.

Material delivered from the machine is received upon the first section, flipped onto the next following section, and so on until it is delivered from the last section in the string. Alternate sections may be actuated to flip and advance material, or the actuation may be eifected of every third section. The air pressure required is low, and timing by means of solenoid valves controlled in common, or by means of the single four-way valve 12g, can be accomplished automatically and as rapidly as required.

I claim as my invention:

1. A conveyor unit for flipping successive batches of particulate material in a given sense along a given path from its receiving end past its discharge end, comprising a sheet of relatively inelastic material extending from end to end of the unit, and flexible lengthwise, means to anchor the discharge end of said sheet, leaving it otherwise free to flex, means defining a plurality of interconnected and substantially inelastic bladders disposed transversely above said sheet, at longitudinally spaced intervals, and secured at their transverse edges to said flexible sheet of material, and means for admission of air under pressure to the bladders, to inflate them and so to curl up the sheet of material, and for discharge of air to deflate them.

2. A conveyor unit for flipping successive batches of particulate material in a given sense along a given path from its receiving end past its discharge end, comprising a plurality of horizontally disposed, transversely direc-ted plates hingedly connected, means to anchor the plate at the discharge end to retain it flatwise, the remaining plates being free to curl upwardly or to lie flat, an inflatable bladder overlying the plate next to said anchored plate, and a similar inflatable bladder overlying each alternate plate towards the discharge end, and means for admission of air under pressure to the several bladders, to inflate them and so to curl up the unit as a Whole, and for discharge of air therefrom, to deflate them, for restoration of the unit to its flat condition.

3. A conveyor for flipping batches of particulate material in a given sense along a given path from its receiving end past its discharge end, comprising successive units each including a plurality of transversely directed plates hingedly joined in successive edge-to-edge relationship, whereby they may lie flat and generally in a common plane, or may curl. upwardly, means to anchor a terminal plate of each unit against departure from-its flat disposition, a plurality of transversely directed inflatable but substantially inelastic bladders located above and secured along their respectively opposite edges to said terminal plate and to each alternate plate in each unit, and extending at their edges past the edges of. the intermediate plates, to curl up the several plates from their flat disposition by inflation, and means for admission of air under pressure to inflate the bladders of one unit to deliver material which has been deposited thereon onto the next unit as the latter lies flat, and so sequently to inflate the bladders of said next unit. for further advance of the material.

4. A multiple unit conveyor as in claim 3 including a drawbar extending beneath each unit, and pivotally connected to the terminal plate of that unit and of the adjoining unit, for swinging transversely of the direction of advance.

5. A conveyor unit comprising a terminal plate directed transversely of the direction of advance, and held generally flat upon a supporting surface, a plurality of plates similarly directed and disposed, for the reception;

of material, generally flat in edge-to-edge relationship to said terminal plate and to each other, hinge means connecting the adjoining edges of successive plates, inflatable but substantially inelastic bladders directed transversely above that plate which adjoins the terminal plate and above each alternate plate, and each secured along its respective edges to the intervening plates, inwardly of the letters. edges, and means for admission of air under pressure to inflate said bladders to curl upwardly the second plate from the terminal plate and successive plates from the respectively preceding plates, and alternatively for discharge of air to deflate said bladders to flatten the plates and bladders of the conveyor unit.

6. A conveyor unit comprising a terminal first plate elongated transversely of the direction of advance, an even number of similar additional plates placed successively in edge-to-edge relationship to the terminal plate and to one another, and hingedly joined along their adjoining edges, means to hold the terminal plate flat upon a supporting surface, an inflatable but substantially inelastic bladder extending above and generally in the same transverse direction as the second and all evennumbered plates, and overlying the hinge joints of the same with the two adjoining odd-numbered plates, means to secure each bladder along its edges to the respective odd-numbered plates, and means for admission of air under pressure to inflate all such bladders of the convevor unit, and for discharge of air to deflate the same.

7. A conveyor unit as in claim 6, wherein a drawb-ar is pivotally connected to each terminal plate for swing ing transversely of the direction of advance, and is of a length to extend beneath the unit for securement to the terminal plate of an adjoining conveyor unit, said drawbar constituting the means to hold the terminal plate flat.

8. A conveyor unit as in claim 6, including an apron upstanding from the third plate and extending thence in the direction of advance, of a size and length to overlie the bladder above the second plate and, when the section is curled up by inflation of the bladders, to extend beyond the edge of the terminal plate.

9. A conveyor unit as in claim 8, including flexible flanges upstanding at the side edges of the conveyor unit, said flanges being secured to the respective ends of the apron.

10. A conveyor unit as in claim 6, wherein the several bladders are formed as free portions above the evenvnumbered plates of a double-thickness sheet extending from the terminal plate to the most distant plate, and secured to each thereof and to all odd-numbered plates.

11. A conveyor unit as in claim 10, wherein the sheets extend upwardly at the side edges of the unit, as flexible side flanges.

12. A conveyor unit as in claim 6, including flexible flanges upstanding at the side edges of the conveyor unit, and means to retain said flanges generally upright while the plates lie flat.

13. A conveyor unit as in claim 1, wherein the means for admission of air is located to admit initially to the bladder nearest the units anchored discharge end, and includes air passageways connecting successive bladders, in order towards the units opposite receiving end.

14. A conveyor unit for flipping successive batches of particulate material in a given sense from its receiving end past its discharge end, comprising a plurality of inflatable bladders disposed generally horizontally, transversely of the path of advance of the material, in parallel, spaced relation, sectional areas of substantial stiffness as compared with the upper walls of the bladders, disposed intermediate and joined to the bladders along their transverse edges, for relative hinging movement, to join the sectional areas and bladders into a complete unit, means to anchor the discharge end of the unit, the lower Wail of each bladder having inherently lesser flexibility than its upper wall, and means for admission of air 25 under pressure to the several bladders, to inflate them, and for discharge of such air, to deflate them, whereby to curl up the free end of the unit as a whole, or to flatten the same, respectively.

15. A conveyor unit for flipping successive batches of particulate material in a given sense along a given path from its receiving end past its discharge end, comprising a stifler but flexible lower lamina extending the length of the unit, a less stifr but flexible upper lamina overlying said lower lamina and secured thereto along all its edges, and in transversely directed areas intermediate its ends, which alternate with non-connected areas defining inflatable bladders, there being passageways connecting the several bladders, means to anchor one end of the unit against upward curling from its relaxed flat condition, the laminae being otherwise free to curl up wardly, and means for admission or" air under pressure to the bladders, to inflate them, and by reason of the diiterence in stiffness of the two laminae to curl up the same, and for discharge of air to defiate them, to allow the unit to return to its flat condition.

References Cited in the file of this patent UNITED STATES PATENTS 2,508,303 Sturtevant May 16, 1950 

